freebsd-skq/sys/dev/vmware/vmci/vmci_utils.h
mp 2b8899b47a Update VMCI license based on comments from core, the FreeBSD Foundation,
and VMware legal:
- Add a dual BSD-2 Clause/GPLv2 LICENSE file in the VMCI directory
- Remove the use of "All Rights Reserved"
- Per best practice, remove copyright/license info from Makefile

Reviewed by: imp, emaste, jhb, Vishnu Dasa <vdasa@vmware.com>
Approved by: VMware legal via Mark Peek <markpeek@vmware.com>
Differential Revision:  https://reviews.freebsd.org/D14979
2018-04-08 01:32:56 +00:00

44 lines
909 B
C

/*-
* Copyright (c) 2018 VMware, Inc.
*
* SPDX-License-Identifier: (BSD-2-Clause OR GPL-2.0)
*
* $FreeBSD$
*/
/* Some common utilities used by the VMCI kernel module. */
#ifndef _VMCI_UTILS_H_
#define _VMCI_UTILS_H_
/*
*------------------------------------------------------------------------------
*
* vmci_hash_id --
*
* Hash function used by the Simple Datagram API. Hashes only a VMCI ID (not
* the full VMCI handle). Based on the djb2 hash function by Dan Bernstein.
*
* Result:
* Returns guest call size.
*
* Side effects:
* None.
*
*------------------------------------------------------------------------------
*/
static inline int
vmci_hash_id(vmci_id id, unsigned size)
{
unsigned i;
int hash = 5381;
for (i = 0; i < sizeof(id); i++)
hash = ((hash << 5) + hash) + (uint8_t)(id >> (i * 8));
return (hash & (size - 1));
}
#endif /* !_VMCI_UTILS_H_ */